Five years in: The effects of legalization in Colorado and Washington state

In 2012, the states of Colorado and Washington became the first in the US to legalize cannabis for recreational use. Critics feared it would attract criminal elements, and that it would lead to increases in impaired driving incidents and youths being exposed to the drug, while advocates hoped it would lead to an economic boom, and an end to the criminalization of cannabis users.

This November marks the five year anniversary of legalization in both states. In that time a number of studies, surveys, and statistics have been published that provide a view into the range of effects that have been observed since the new regime was implemented. Here are some highlights:

Criminal elements

Prediction: Criminal elements would be attracted.

Observation: Mixed results, but overall that myth was busted.

A report published in 2016 found that cannabis-related crime had increased in Washington state post legalization. The report was based on data from both Spokane Valley and Seattle police departments, and it showed a rise in unlicensed distribution and possession of illegal cannabis following legalization, most of which was destined for states where prohibition was still in force.

However those statistics represent only a small portion, geographically speaking, of just one state. On the whole, crime statistics for Washington state reached a 40-year low in 2014, with violent crime down 10 percent and a 13 percent drop in the state’s murder rate. Colorado also saw decreases in overall crime rates, violent crimes, and property crimes.

Impaired driving

Prediction: Accidents and impaired driving incidents would increase.

Observation: Confirmed (mostly).

A study produced by the Insurance Institute for Highway Safety, which has received criticisms from legalization advocates, found that in 2014 (the year in which the first legal recreational cannabis shops actually opened for business) overall claims for traffic incidents rose by 14 percent in Colorado, and 4.6 percent in Washington.

While a certain amount of annual increase was expected regardless of legalization, even after researchers accounted for controls including rates of increase in nearby states where cannabis remained illegal, a rise of 2.7 percent was attributed to the legalization of cannabis.

But reports emphasize that while more drivers who had been involved in insurance claims in Washington and Colorado admitted to consuming cannabis before operating their vehicle, that may not reflect actual changes in usage, due to extremely limited data prior to legalization.

Nevertheless a correlation has been observed, showing a disproportionate increase in traffic-related insurance claims in states where cannabis has been legalized.

Youth exposure

Prediction: Minors would start using cannabis (more than they were already).

Observation: Myth busted.

Earlier this year a think tank working for Washington’s state legislature produced a report showing overall decreases in youth cannabis usage rates.

The report was based on survey data from the state’s Department of Health, which polled for usage among students in grades six, eight, ten, and twelve. The results of the survey showed decreased usage by students in all four grade levels. For example, students in the tenth grade responded at